CONDUCT OF PERFUSION

1. CONDUCT OF PERFUSION October 16, 2003 Brian Schwartz, CCP

2. PURPOSE OF CPB • PROVIDE SURGEONS WITH A MOTIONLESS AND BLOODLESS FIELD • PROVIDE PROTECTION TO VITAL ORGAN SYSTEMS

3. Your Objectives • Understand the components of the CPB circuit • Understand the sequence for assembly of the circuit • Able to calculate the predicted hemoglobin and hematocrit • Understand the determinants of oxygen consumption

4. Conduct of Perfusion • Purpose of CPB: support patient’s metabolic needs while providing a motionless, bloodless cardiac surgical field • Parameters that must be met: • Proper flow rate • Oxygen delivery • Carbon dioxide removal • Anticoagulation • Temperature • Blood pressure • Blood recovery

5. Components of the CPB Circuit • Oxygenator • Heat exchanger • Venous reservoir • Gas flow meter • Variety of pumps • Tubing • Cannulae • Hemoconcentrator • Alarms • Drugs

6. Assembly • The set up is dependent upon: • Procedure • Patient size • Surgeon’s preference • Perfusionist’s preference

7. CONDUCT OF PERFUSION • WE ARE TALKING ABOUT OUR DUTIES AND RESPONSIBILTIES PRE-OP, INTRA-OP, AND POST-OPERATIVELY

8. THE PERFUSIONIST’S TIME LINE • GET A HANDLE ON THE SCHEDULE • REVIEW PATIENT’S CHART • SELECTION OF DISPOSABLE EQUIPMENT • ASSEMBLE HLM • PLUG IN POWER AND GAS LINES • PLUG IN HEATER/COOLER (WATER TEST)

9. Time Line (cont) • CO2 flush the circuit • Prime the circuit • Test all occlusions • Check list • Perform all quality controls • ALWAYS BE PROPARED TO GO ON CPB

10. TIME LINE (CONTINUED) • PRIME CIRCUIT • PERFORM CHECK LIST • ADMINISTRATION OF HEPARIN • INITIATION OF CPB • TERMINATION OF CPB • ADMINISTRATION OF PROTAMINE • BREAKDOWN AND CLEANUP OF HLM

11. PRE-BYPASS CALCULATIONS • PREDICTED HEMATOCRIT • 70 X KG = TBV • TBV X HCT = TRBC • TBV + PRIME + ANES. DRIPS = TCBV • TRBC/RCBV = DILUTIONAL HCT

12. PRE-BYPASS CALCULATIONS • HCT IF SEQUESTERING BLOOD • TRBC – { 500 cc x HCT } / TCBV – 500 cc

13. HEPARIN ADMINISTRATION • DESCRIBED AS AN ANTICOAGULANT • MUST FULLY ANTICOAGULATE PATIENT • SITE OF ACTION: ATlll AND INHIBITS FACTORS IX AND XI OF THE CLOTTING CASCADE • GIVE 300-400 UNITS/KG • IN RIGHT ATRIUM OR CENTRAL LINE

14. HEPARIN ( CONTINUED ) • HALF LIFE = 1-2 HOURS • 3-5 MINUTES AFTER ADMINISTERING TAKE AN ACT…..MUST BE >480 SECONDS • SOME PATIENTS MAY BE HEPARIN RESISTENT • THEY ARE ATIII DEFICIENT • GIVE FRESH FROZEN PLASMA

15. CANNULATION • SURGEONS NOW PLACE THE CANNULAE INTO THE HEART • VENOUS CANNULAE • IN RIGHT ATRIUM WITH 2 STAGE • SINGLE STAGE IN THE IVC AND THE SVC

16. CANNULATION • ARTERIAL CANNULAE • AORTA OR FEMORAL ARTERY • RETROGRADE CARDIOPLEGIA • ANTEGRADE CARDIOPLEGIA • VENT

17. PURPOSE OF VENT • PLACED IN THE AORTIC ROOT OR IN THE LEFT VENTRICLE • USED TO PREVENT DISTENTION OF THE HEART • USE A ONE-WAY VALVE

18. INITIATION OF BYPASS • SURGEONS READY TO BEGIN CPB. THEY WILL TELL YOU TO “GO ON” • ALWAYS REPEAT COMANDS BACK TO AVOID MISTAKES • PUT 02 ON 100%, SWEEP ON, REMOVE ARTERIAL CLAMP, SLOWLY TURN PUMP ON. CAREFULLY MONITOR ARTERIAL LINE PRESSURE !!!!!!!!

19. BYPASS • UNCLAMP VENOUS LINE AND INCREASE FLOW TO YOUR 2.4 INDEX • IF YOU SENSE A HIGH LINE PRESSURE AS YOU INITIATE BYPASS…IMMEDIATELY TERMINATE BYPASS!!!!!!

20. CAUSES OF HIGH AORTIC LINE PRESSURE • KINK IN THE A-LINE • CANNULAE IMPROPERLY POSTIONED • CROSS-CLAMP TOO CLOSE TO CANNULAE • ARTERIAL CANNULAE TOO SMALL • SYSTEMIC PRESSURE TOO HIGH • AORTIC DISECTION • ARTERIAL FILTER OBSTRUCTED

21. CAUSES OF POOR VENOUS RETURN • KINK IN VENOUS LINE OR CANNULA • AIRLOCK • OXYGENATOR IS NOT POSITIONED LOW ENOUGH • VENOUS CANNULA PLACED TO FAR DOWN INTO THE CAVA • VENOUS CANNULA FALLS OUT

22. CHATTERING • A TERM USED IF THE HEART IS COMPLETELY EMPTY AND YOU SEE THE VENOUS LINE JUMPING AROURD • CHATTERING IS CAUSED BY EXCESSIVE NEGATIVE PRESSURE IN THE VENOUS LINE CAUSING A SUCTION EFFECT….SIMPLY PLACE A CLAMP (PARTIALLY) ON THE VENOUS LINE TO REDUCE THE NEGATIVE PRESSURE

23. SAFTEY CHECKS TO DO ON BYPASS • FLOWING AT PROPER RATE • A-LINE PRESSURE IN NORMAL • OXYGEN IS ON AND THAT ARTERIAL BLOOD IS RED….COMPARE A/V LINES • O2 SAT’S NORMAL • MAP BETWEEN 50-70 • TEMP’S • ACT>480 • MAKE SURE ALL SAFETY DEVICES ARE ON

24. MONITORING • EKG • WHILE THE CROSS-CLAMP IS ON THERE SHOULD BE NO ACTIVITY • WHEN CLAMP COMES OFF, BE ON THE LOOK OUT FOR ST ELEVATIONS, V-TACH, AND V-FIB • PA PRESSURES • CIRCUIT • OPERATING TEAM • KEEP COMMUNICATION OPEN • TRAFFIC AROUND PUMP

25. CHARTING • VITAL SIGNS MUST BE TAKEN EVERY 15 MINUTES • ACT’S MUST BE TAKEN EVERY 30 MIN • BLOOD GASES MUST BE TAKEN EVERY 30 MINUTES OR AFTER CHANGES HAVE BEEN MADE • FIRST BLOOD GAS SHOULD BE TAKEN 5-10 MINUTES AFTER CPB • DON’T FORGET TO GET A WARM GAS BEFORE TERMINATING BYPASS

26. NORMAL ARTERIAL GAS • pH: 7.35-7.45 • p02: Greater than 100 • 02 Sat: 96-100% • K+: 3.5-5.3 • BICARB: 22-28 MEQ/L • BE: -2.5 TO + 2.5

27. NORMAL VENOUS GAS • pH: 7.35-7.39 • P02: 38-42 • 02 Sat: 65-75% • pCO2: 44-48mmHG • Bicarb: 22-28 mmHG • BE: -2.5 to +2.5

28. Determine Oxygen Consumption • Oxygen content=1.34 x Hb x Sat + .003xp2 • Oxygen Capacity =1.34 x Hb + .003 x pO2 • Oxygen Saturation = O2 content/ Capacity • Oxygen Consumption= aO2 content – vO2 content x flow (L/min) X 10

29. CALCULATE AMOUNT OF BICARB TO GIVE • WT (KG) X BASE DEFICIT X .3 • EQUATION #1 DIVIDED BY 2 = AMOUNT OF BICARB TO GIVE EXAMPLE: 70 X 3 X .3 = 63 63 / 2 = 32 mEq

30. POST BYPASS • MONITOR PATIENTS HEMODYNAMICS • NEVER DISMANTLE PUMP UNTIL CHEST IS CLOSED • PROTAMINE • MANY PATIENTS HAVE REACTION • TURN OFF PUMP SUCKERS • MONITOR PA AND MAP

31. PROTAMINE REACTIONS • TYPE I • SYSTEMIC HYPOTENSION • REDUCED SVR • TYPE II • ANAPHYLACTIC REACTION RESULTING IN HYPOTENSION, BRONCHOSPASM, AND EDEMA • TYPE III • CATASTROPHIC PULMONARY VASOCONSTRICTION WITH INCREASED PA PRESSURES, HYPOTENSION, DECREASED LA PRESSURES, AND DILATED RIGHT VENTRICLE

32. CLEAN-UP • SEND ALL BLOOD TO CELL SAVER • DISMANTLE TUBING • CLEAN UP PUMP FOR ANY BLOOD STAINS • PAPER WORK • SET UP BACK UP PUMP • SET UP BACK UP CELL SAVER